Energy efficiency of an integrated refrigeration and air-conditioning system using test and site measurements

From 2020 through 2022, Daikin Europe aims to investigate the reduction of CO2 emissions and the impact of the raw materials used, by monitoring an integrated system installed in supermarkets across Europe, having engaged in an EU funded LIFE project called NaturalHVACR4Life. The integrated system studied throughout the project and this paper is the CO2 Conveni-pack, a Daikin product, which provides simultaneous refrigeration and space heating or cooling with the possibility of heat recovery. The Total Equivalent Warming Impact (TEWI) of the integrated unit was compared to an R410A unit using test measurements, where, the CO2 unit was found to emit significantly lower emissions over a period of 10 years. Furthermore, energy performance of a unit operating in a real shop in the EU has been discussed. The delivered energies by the unit in these shops were calculated using a 'Compressor Curve' method, which estimates the refrigerant mass flow in absence of expensive flow meters. This method has also been presented and discussed. Finally, a comparison in the peak and off-peak operation of the units at the two sites has been presented and discussed.